Internal combustion engine



Filed July 22, 1930 Patented Jan. 22, 1935 esa-s33 INTERNAL COIWBUSTIONENGINE Lionel M. Woolson, deceased, late of Detroit, Mich, by Emma F.Woolson, executrix, Bloomfield Village, Mich., assignor to Packard MotorCar Company, Detroit, Micln, a corporation of Michigan Application July22, 1930, Serial No. 469,895

9 Claims.

This invention relates to internal combustion engines and moreparticularly to fuel injection mechanism for engines 'of the Dieseltype.

It is a general object of the present invention 5, to provide a noveland improved fuel injection mechanism for internal combustion engines.

More particularly it is an object of the invention to provide a fuelinjection mechanism where-' in the quantity of fuel injected in eachcylinder of the engine is regulated in accordance with the temperatureof that cylinder.

An important feature of the invention resides 'in mounting fuelinjection mechanism on each cylinder in such a manner that any increasein length of a cylinder from expansion results in a decrease in thequantity of fuel delivered thereto.

Another important feature of the invention consists in so mounting thefuel injection mechanism that it is inherently subject to a reduction indelivered volume of fuel as the cylinder expands and to further providemultiplying linkage also actuated by expansion of the cylinder toaugment the inherent fuel regulation.

Other and further features and objects of the invention will be moreapparent to those skilled in the art upon a consideration of theaccompanying drawing and following specification wherein is disclosed asingle exemplary embodiment of the invention with the understanding,however, that such changes may be made therein as fall within the scope.of the appended claims without departing from the spirit of theinvention.

In said drawing:

The single figure is an axial section through one cylinder of amulti-cylinder, radial type, Diesupports the cylinder at the irmer orend opposite the head 12, as clearly shown, and wherein suitableclamping rings 13 secure the cylinder rigidly to the crank case.

The fuel injection mechanism is of the type which includes a separatepump for each cylinder shown in general by the reference character 15and'intended to deliver fuel in the liquid state into the cylinder priorto each explosion. This is sometimes known as-solid fuel injection. Thepump comprises essentially a pump barrel 16 radially disposed and havingits axis substantially parallel to the axis of the cylinder. A solid rod17 forms the plunger or piston of the pumpand is arranged to reciprocatewithin the barrel and to discharge oil through the checkvalves 18 and 19into a head 20 provided with a projection 21 which extends into theengine cylinder just above the top position of the piston 22. Thisprojection 21 sel engine, the section being taken on the axis of thefuel injection mechanism and wherein parts not distinctly related to theinvention are shown in elevation.

The present invention, for convenience in disclosure, is shown inconnection with a radial cylinder engine of the Diesel type such asparticularly constructed for aviation use although it will be apparentthat it can be used with equal facility with other types of engines bothof the air and water 'cooled types. This inventi particularly relates-tothat type of Diesel engine disclosed in the copending application ofLionel L. Woolson, Serial No. 358,899, filed April29, 1929, but is notnecessarily limited to such types of engines.

For the sake of convenience, but a single cylinder 10 has been showntogether with a fragment ll of a substantially cylindrical crank casewhich may be provided with a spring-controlled nozzle 20 head 23 'whichnormally is substantially closed and provides a resistance to the oildelivered by the pump.

Just below the check valve 18 there are a plurality of inlet ports 25through the wall of the pump barrel. These ports are arranged in a ringaround the periphery of the barrel and open into an annular chamber 26surrounding the pump barrel and always supplied with fuel oil at alow-pressure by any suitable means. The piston or plunger of the pump isarranged to reciprocate from a position below the ports 25 to a positionabove these ports. It will be seen that when it is withdrawn below theports oil will enter through them and fill the barrel below the checkvalve 18, and that when the piston rises or moves outwardly it will notbegin pumping oil through the atomizing nozzle until it has first closedthe inlet ports 25. It can, therefore, be said that the pump is of thetype wherein the quantity of' discharge is dependent on the displacementof oil beyond the inlet ports. It is not so much the length of thestroke as the position of the stroke of the plunger which controls thequantity of discharge. The eilective stroke 4 of the pump plunger isthat portion which takes place after the ports 25 are covered.

The pump plunger is adapted to be reciprocated, in the present instance,from a cam. ring 30 which rotates in an extension of the crankcase andis suitably driven from some rotating part of the engine, not shown.Bearing on the Vided, along its upper surface, with a groove 35 5 inwhich the lower end of a strut 36 bears. This strut is pivoted at 3'7 tothe lower end of a connecting rod 38 the upper end of which bears, witha suitable joint, on the lower end of the cross head slide 39reciprocable in a sleeve 40 seated in portion 42 of the crankcaseextension.

Means, fully described and shown in application Serial No. 358,899,previously referred to, are provided for adjusting the ends of thestruts along the grooves to vary the strokes and the positions of theupper ends of the plungers 17 in respect to the inlet ports 25 forchanging the fuel consumption of all of the cylinders simultaneously tothus vary the speed and/or power of the engine.

A coil spring 43 surrounds the pump barrel 16 and bears atits upper endon an enlargement thereof and at its lower end on a head 45 on the lowerend of the plunger 17 to normally maintain the plunger in its retractedposition. This spring is housed in a sleeve 47 secu ed to the main bodyof the pump. The spring causes the plunger 17 to be biased in thedirection of the cross head 39 which is co-axial therewith.

The whole pump mechanism, but particularly the barrel part, is supportedfrom the head end of the cylinder where it is seen to-be secured intoposition by the bolts 50. The operating mechanism for the pump is all atthe crankcase end of the cylinder. This arrangement provides an inherentmeans for reducing the quantity of oil supplied to each cylinder as itstemperature increases and itwill be seen that expansion resultant froman increase in temperature will move the pump barrel radially outwardlywith respect to the crankcase and, therefore, will cause the pumpplunger to reciprocate through a range closer toward the center of theengine and hence to have less displacement above the intake ports 25.This produces an automatic adjustment which insures that any cylinderswhich become overheated will of themselves reduce their fuel supply topermit a resumption of normal operating temperature and to cause anyexcessively cooled cylinders to take up the load which will becomeevenly distributed among all of the cylinders. It is self evident thatthe fuel injection mechanism will remain at a substantially constanttemperature irrespective of changes in the cylinder temperatures.

In some cases this inherent regulation of fuel supply may be inadequateto equalize the cylinder temperatures and it can be augmented bysuitable linkage mechanism controlled by the expansion of the cylinder.One convenient way of doing this' is shown in the drawing wherein a pairof links 52 and 53 are pivoted together at 54 to form a toggle. Theupper link is pivoted at 55 to the housing for the spring 43 and thelower link at 56 to a boss on the crankcase part 42. Likewise pivoted at54 is one end of a wedge member 58 which extends. between the pointedend 59 of the plunger head 45 and the pointed head 60 of the cross head.This wedge member increases in thickness from the pivot outwardly asshown. It will be clear that as the cylinder expands the toggle will bestraightened, the

wedge member 58 forced to the right and the pump plunger retracted toreduce its effective stroke. On cooling of the cylinder a converseaction takes place as will be readily understood.

The major portion of the wedge member 58 is enclosed in the tubularhousing 65 secured at its inner end to a boss on the bushing 40 and having a sliding fit over the inner end of the spring housing 47.

It will be clear that other mechanical expedients will be equallyeffective for augmenting the inherent fuel regulation of the type ofpump shown and it is the intent of the following claims to cover allmechanical equivalents of this structure for essentially the inventionresides in inherent fuel regulation in accordance with cylindertemperature and means for augmenting this inherent regulation. It willbe appreciated that the expansion of the cylinder and its increase inlength is a function of the temperature so that it can be said that theregulation of fuel supply is dependent on cylinder temperature.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

1. In an engine of the fuel injection type, in combination, a cylinderof the air cooled type, a fuel injection pump barrel secured to thecylinder near one end, anfinlet port in said barrel, a plunger operatingin. said barrel to deliver fuel in quantity depending on its extent ofmovement beyond the inlet port on its delivery stroke, actuating meansassociated with the opposite end of said cylinder to move the plunger onits delivery stroke, means toreturn the plunger after delivery, meansnormally spacing the plunger and actuating means and means actuated byan increase in the distance between the two ends of the cylinder fromheat expansion to reduce the spacing between said actuating means andthe plunger.

2. In an engine of the fuel injection type, having a cylinder, atplunger pump substantially parallel to the cylinder and of the typewherein the position of the plunger at the end of the injection strokedetermines the quantity of fuel delivered, the combination of meansactuated by the expansion of the cylinder by heat to withdraw theplunger from the pump barrel, and further means actuated by the increasein length of the cylinder by expansion to augment said withdrawing.

3. In an engine of the fuel injection type, in combination, a cylindermounted on a crankcase, a plunger pump barrel fastened to the cylindernear its head end, a plunger in said barrel, a spring to move saidplunger toward said crankcase, an operating mechanism in said crank-casefor said plunger, means normally spacing the plunger and its operatingmechanism, a linkage having its ends associated with the opposite endsof the cylinder, and means actuated by said linkage when the cylinderexpands by heat to reduce the spacing between said plunger and operatingmechanism.

4. In an engine of the fuel injection type, in combination, a cylindermounted on a crankcase, a plunger pump barrel fastened to the cylindernear its head end, a plunger in said barrel, a spring to move saidplunger toward said crankcase, an operating mechanism in said crankcasefor said plunger, a linkage having its ends associated with the oppositeends of the cylinder,

ateness tern operated by the expansion of each cylinder and cf eachcylinder and having a fuel inlet port near its outerend, a plunger ineach barrel and determining the quantity of fuel delivered by thedistance its end is projected beyon'd the inlet port, a part movable insaid crankcase for operating each-plunger, mechanism actuated by theexpansion of each cylinder and means actuated by said mechanism andbetween each pump plunger and its operating part to reduce the distancebetween the adjacent end' of said plunger and said plunger operatingpart.

6. In a fuel injection engine, the combination, a plurality of radiallydisposed cylinders, a crankcase secured to the inner ends of thecylinders, a radial fuel pump barrel attached to the outer end at eachcylinder and having a fuel inlet port near its outer end, a plunger ineach barrel and determining the quantity of fuel delivered by thedistance its end is projected beyond the inlet port, a part movable insaid crankcase for operating each plunger, means to adjust the deliveryof all pumps simultaneously to vary engine speed cr-power, wedge meansbetween each plunger and part and a linkage positioning each wedge andadapted to movethe same longitudinally with changes in temperature ofthe associated cylinder whereby an overheated cylinder has its fuelsupply automatically reduced below that of other cylinders to reduce theheating.

'1. In a fuel injection engine, in combination, a plurality of radiallydisposed cylinders, a crankcase secured to the inner ends of thecylinders, a radial fuel pump barrel attached to the outer end of eachcylinder and having a fuel inlet port near its outer end, a plunger ineach barrel and determining the quantity of fuel delivered by thedistance its end is projected beyond the inlet port, a part movable insaid crankcase for operating each plunger multiplying lever sysrel anddetermining the quantity of fuel injected in accordance with the extentof its movement beyond the inlet port toward the head end, and meanscarried by the crankcase to actuate and position said plungers, thecross-section and stroke of each plunger being determined in respect tothe thermal expansion of the cylinder to prevent overheating of any onecylinder by the proper reduction in' fuel delivered thereto by theconsequent withdrawal of the plunger whereby the load is equalized amongall cylinders.

9. In a fuel injection engine, in combination, a plurality of separatecylinders, a fuel injection device for each cylinder, means to adjustthe said devices simultaneously to vary the speed of the engine andalways supply the same nominal quantity of fuel to each cylinder, andregulating means actuated by expansion of any cylinder to independentlyreduce the quantity of fuel delivered to that cylinder by the injectiondevice therefor, progressively as its temperature increases while thenominal fuel delivery to that cylinderremains under control of theaforesaid adjusting means.

EMMA F. WOOL-SON, Executn'a: o! the Estate of Lionel M. Woolson,

Deceased.

